9.3.1.

(1) Except as provided in Sentence (2), nominally unreinforced concrete shall be designed, mixed, placed, cured and tested in accordance with CAN/CSA-A438, “Concrete Construction for Housing and Small Buildings”.

(2) Nominally unreinforced site-batched concrete shall be designed, mixed, placed and cured in accordance with Articles 9.3.1.2. to 9.3.1.9.

(3) Except as provided in Sentence (4), reinforced concrete shall be designed to conform to the requirements of Part 4.

(4) For flat insulating concrete form walls not exceeding 2 storeys, and having a maximum floor to floor height of 3 m, in buildings of light frame construction containing only a single dwelling unit, the concrete and reinforcing shall comply with Part 4 or,

(a) concrete shall conform to CAN/CSA-A23.1, “Concrete Materials and Methods of Concrete Construction”, with a maximum aggregate size of 19 mm, and

(b) reinforcing shall,

(i) conform to CAN/CSA-G30.18-M, “Billet Steel Bars for Concrete Reinforcement”,

(ii) have a minimum specified yield strength of 400 MPa, and

(iii) be lapped a minimum of 450 mm for 10M bars and 650 mm for 15 mm bars.

(1) Cement shall meet the requirements of CAN/CSA-A3001, “Cementitious Materials for Use in Concrete”.

(1) Concrete in contact with sulfate soil, which is deleterious to normal cement, shall conform to the requirements in Clause 15.5 of CAN/CSA-A23.1, “Concrete Materials and Methods of Concrete Construction”.

(1) Aggregates shall,

(a) consist of sand, gravel, crushed rock, crushed air-cooled blast furnace slag, expanded shale or expanded clay conforming to CAN/CSA-A23.1, “Concrete Materials and Methods of Concrete Construction”, and

(b) be clean, well-graded and free of injurious amounts of organic and other deleterious material.

(1) Water shall be clean and free of injurious amounts of oil, organic matter, sediment or any other deleterious material.

(1) Except as provided elsewhere in this Part, the compressive strength of unreinforced concrete after 28 days shall be not less than,

(a) 32 MPa for garage floors, carport floors and all exterior flatwork,

(b) 20 MPa for interior floors other than those for garages and carports, and

(c) 15 MPa for all other applications.

(2) Concrete used for garage and carport floors and exterior steps shall have air entrainment of 5 to 8%.

(1) For site-batched concrete, the concrete mixes described in Table 9.3.1.7. shall be considered acceptable if the ratio of water to cementing materials does not exceed,

(a) 0.45 for garage floors, carport floors and all exterior flatwork,

(b) 0.65 for interior floors other than those for garages and carports, and

(c) 0.70 for all other applications.

(2) The size of aggregate in unreinforced concrete mixes referred to in Sentence (1) shall not exceed,

(a) 1/5 the distance between the sides of vertical forms, or

(b) 1/3 the thickness of flatwork.

(1) A 40 kg bag of cement contains 28 L.

(1) Admixtures shall conform to ASTM C260, “Air-Entraining Admixtures for Concrete”, or ASTM C494 / C494M, “Chemical Admixtures for Concrete”, as applicable.

(1) When the air temperature is below 5°C , concrete shall be,

(a) kept at a temperature of not less than 10°C or more than 25°C while being placed, and

(b) maintained at a temperature of not less than 10°C for 72 h after placing.

(2) No frozen material or ice shall be used in concrete described in Sentence (1).